Pyrone dye



I. Patented Apr. 7, 1925.

UNITED STATES 1,532,790 PATENT OFFICE.

MAX WEILER, F ELBERFELD, GERMANY, ASSIGNOR T0 FARBENFABRIKEN VORM.

FRIEDR. BAYER AND 00., OF LEVERKUSEN, NEAR COLOGNE-ON-THE-RHINE, GER- MANY.

PYRONE DYE.

No Drawing.

To all whom.- t may concern:

Be it known that I, MAX WEILER, a citizen of Germany. residing at .Elberfeld, in the State of Prussia, Germany, have invented 6 new and useful Improvements in Pyrone Dyes, of which the following is a specification.

The present invention relates to the manufacture and production of new and valuable dyestufis of the pyrone series capable of being chromed after dyeing and which in the shape of either their leucocompounds or the dyestuffs themselves can be further sultonated. They have most probably the following general formula: I

in which X includes hydrogen, alkyl and the carboxylic group; Y and X include hydrogen and the hydroxy group; Z includes hydrogen and the carboxylic group, and R represents an aromatic nucleus.

The new dyes are after being dried and the carbinol carbon atom and oxidizing the resulting leucocompounds respectively sulfonatiug these leucocompounds or the dye- IO stuffs themselves in the usual manner.

In order to illustrate my new process more fully the following example is given, the parts being by weight:

15 parts of 2.6-diclilorbenzaldehyde and 28 parts of 2.4-dihydroxy-3-methylbenzoic pulverized generally red to yellow to green- Application filed February 1, 1924. Serial No. 690,087.

acid (obtained by carbonization of 2.6-dihydroxytolu'ene melting point 206207 C.) are dissolved in a strong sulfuric acid and stirred until both components are ahnost completely converted into the leuco acid. The melt is poured on ice and the leuco acid which separates is filtered off It is almost insoluble in water and gives with "ferric chloride at reddish-blue coloration. For the production of the dyestufl it is not necessary to isolate the leuco acid but use the melt directly. For this purpose 7 parts of sodium nitrite, if necessary after an addition of sulfuric acid (100 per cent), are introduced into the melt and it is stirred until the formation of the dyestufi is complete. The melt is then poured on ice and the dyestuff thus obtained in the form of a red powder is filtered oil.

The new dye is after being dried and pulverized a brown powder soluble with great di'tficulty in hot water with a red-orange coloration but easily soluble in caustic soda solution or sodium carbonate with a scarlet coloration and a strong fluorescence. In

concentrated sulfuric acid a yellow solution is obtained.

It has most probably the formula: J

mordants they turn to an intense purple.

Other oxidizing agents can also be used. c

The above mentioned aldehyde may be replaced by other aldehydes. such as benzaldehyde, ortho-sulfobenzaldehyde, orthochlorobenzaldehyde, 2-chloro-5-sulfobenzaldehycle, 2.6 dichloro 3 hydroxybenzaldehyde, 2.4.6-trichloro-3-hydroxybenzaldehyde, 2 chloro 4 diethylaminobenzaldchyde. 1.? dichloro 2 anthraquinonealdehyde, metachlorobcnzaldehyde, para-chlorobenzaldehyde, 4-chloro-3-sultobenzaldehyde, paranitrobenzaldchyde, para diethylaminobenzaldchydc, etc.

Instead of the 3-methyl-2.4-dihydr0xybenzoic acid, other 2.4-dihydroxybenzoicacids can be used.

The introduction of sulfuric acid groups in the leucocompound or in the dyestuti' itself is for example performed as follows: 8.2 parts of the dried leuco acid (see ex ample) are dissolved in 80 parts of sulfuric acid (100 per cent) and 20 parts of fuming sulfuric acid (65 per cent) are added to it. The liquid is stirred until a sample of the isolated leuco acid is easily and completely soluble in water. The leuco acid gives with ferric chloride a blue-violet coloration. For the conversion of this leuco acid into its dyestuff the compound is diluted with a small quantity of ice or sulfuric acid B). 1.7 parts of sodium nitrite are then added and afterwards stirred under a moderate heating until the formation of the dyestuif is finished. The melt is poured on ice and common salt. The isolated dyestufi' is easily soluble in water and dyes wool from an acid bath a scarlet shade, afterchromed it turns into an intense purple shade. It can also be used for printing. In an analogous manner a sulfuric acid group can also be introduced in the dyestuif itself in which case agreater quantity of fuming sulfuric acid is necessary. The dyestuff thus obtained has the formula:

CH CH:

1. The herein described new dyestuffs of the pyrone series having most probably the following general formula:

in which X includes hydrogen, alkyl and the carboxylic group; Y and X include hydrogen and the hydroxy grou Z in cludes hydrogen and the carboxy ic group ing wool from acid baths from yelloworange to brown and after chroming from red-orange to brown-red shades fast to alkali, fulling and t0 potting, substantially as described.

2. The herein described new pyrone dye having the formula:

which is after being dried and pulverized a brown powder soluble with great difiiculty in hot water with a red-orange coloration and easily soluble in caustic soda solution with a scarlet coloration and a strong fiuorescence; dyeing wool from acid bath scarlet' and afterchromed an intense substantially as described.

3. The herein described new having the formula:

purple shade,

pyrone dye CH: CH;

\/ soul Which dye is after being dried and pulverized a brown powder easily soluble in water with an orange coloration and likewise soluble in caustic soda. solution with a scarlet coloration; dyeing wool from acid bath scarlet and afterchromed an intense red shade, substantially as described.

In testimony whereof I have hereunto set my hand.

MAX 'WEILER. 

